Find the missing number in the sequence below:

Which Number is the odd one out?

A) 7145
B) 2716
C) 5321
D) 4135

A Doctor always sneezes before the rain. Doctor sneezes, Will it rain?

There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes

What makes this number unique: 8,549,176,320?

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different. How do you measure 45 minutes?

A rain drop fell from one leaf to another leaf and lost 1/4th of its volume. It then fell to another leaf and lost 1/5th of the volume. It again fell on another leaf and lost 1/5th of the volume.



This process kept repeating till it fell on the last leaf losing 1/75th of its volume.



Can you calculate the total percentage of loss from the initial volume when the drop has fallen to the last leaf accurate up to two decimal places?

John was writing his first book. After saving the document, he locked his laptop with a password and mentioned some phrases for the hint box.

A friend of his tried opening his laptop but found out that it was password protected. Following is the hint that appeared.
1 mobile 3 books 2 roars 1 night 4 balls 2 lighters 1 ghost 1 hat 3 watches.

Can you help him in cracking the password?

Name a key which is hardest to turn.

Take one out and scratch my head, I am now black but once was red. What am I?